But, that will only affect your ROI, not your annual cash flow.

If you are pleased with the services you received, you're more likely to use that agent again.This can be tough in a young REI career so I'd recommend getting an older agent, someone with a lot of experience and then you should also continue to ask questions on here to get multiple perspectives.

I think you've received some good answers so far but I think the biggest issue always sits with constructing the cap-rate to begin with. 

First of all you don't have as much control of your expenses, and HOA's love to under-collect annually and then sock you with large one-time special assessments to do repairs.  

I personally would make the financial contingency period be based on when you receive final approval or denied - not when the appraisal must be ordered. 

But if you’re keeping your home long term, you will get cashflow right away if you look at the borrowing costs for building the ADU vs the rent you’ll receive. 

A relative found out recently that the lawyer who recorded a lien for them put his law office as the notification address, not their home address.  10 years later when the guy stopped paying, they found out from the records' office that the home foreclosed and they never received notice because it went to the lawyer's office, now non-existent, not their home. 

Do you guys rely on Realtor.com to estimate annual prop. tax based on purchase price? 

I priced meters prior to talking to Universal and when I received their pricing to install meters it was roughly the same price I would pay for just the meter itself.  

But I never received a bill.